HOTMAP: A Tool for Comparing Responses from Different Conditions on an Identical Mesh

During analysis, multiple conditions may produce different responses on an identical mesh, thereby necessitating a comparative analysis. The motivating example for the development of HOTMAP is a comparative analysis of dose rates in the PIONEER instrument cave during the design phase of Oak Ridge National Laboratory’s Second Target Station (STS). This example requires performing radiation transport calculations to determine dose rate fields on a mesh under various operating conditions such as open beam, with various samples in place, or with/without neutron guides present. Each set of operating conditions produces a unique dose rate field, which does not necessarily induce a uniform change across all voxels on the mesh. An analyst developing the necessary radiation shielding for a facility like the STS would be interested in ensuring that adequate shielding is present in all scenarios. HOTMAP was developed to facilitate this process by selecting the limiting response for each voxel among a list of conditions included in the comparison. The response and mesh information, including which condition is responsible for the limiting voxel, is propagated forward and presented in maps that show the limiting dose rate and a map called a HOTMAP that displays which condition is responsible for the limiting dose rate at a particular location on the map. Although this tool was developed based on needs for neutronics analysis at the STS, the use case is broad enough that it may be applicable and beneficial to other users as well.